Researchers found that while physical and mental impairment were no different with the combination, the feeling of intoxication was higher. This heady mix could lead to greater risk taking and more chance of causing injury or embarrassment.

Professor Cecille Marczinski and her colleagues randomly assigned 56 college student participants between the ages of 21 and 33, to one of four groups. One received alcohol, the other energy drinks while a third group was given both together and a final group a non-stimulating soft beverage.

"The findings from this study provide concrete laboratory evidence that the mixture of energy drinks with alcohol is riskier than alcohol alone," said Prof Marczinski. "College students need to be aware of the risks of these beverages. Moreover, clinicians who are working with risky drinkers will need to try and steer their clients away from these beverages."The results were published in the journal Alcoholism: Clinical & Experimental Research.